1. Field of the Invention
This invention relates to an arm motion support apparatus that helps persons having arm related motor function disabilities to perform volitional arm movements and functional exercises.
2. Description of the Prior Art
Devices that have been proposed or are commercially available for supporting arm movement by persons having disabilities related to the motor functions of the arms include non-motorized arm suspension devices which employ springs, powered devices that use lines (cords or wires) or the like to move an arm up and down, and crane arrangements with seven degrees of freedom that use horizontal manipulators and lines for vertical movement.
However, the drawback of these conventional apparatuses is that they do not provide a large degree of control of arm movement, using a simple apparatus and simple control. Apparatuses that are simple do not provide satisfactory control of movement, while those that do provided satisfactory control are highly complex.
Also, with respect to powered devices for aiding autonomous arm movement and functional exercises, when a mechanically driven manipulator is fastened to a patient's arm, the patient has the unpleasant feeling of being restrained by a machine. Thus, there is a need for an apparatus that eliminates such unpleasant feelings and is at the same time lighter, and in which full regard is given to considerations of safety when mistakes are made in movements.
An object of the present invention is to provide an apparatus for supporting arm movement that is structurally light and simple, does not cause patients to feel restrained, can control arm movements with a large degree of freedom and can effectively help patients to make everyday arm movements under their own volition, and to perform functional exercises.